This invention relates to an apparatus for heat recovery and a method for operating the apparatus, and more particularly to an apparatus for heat recovery based on an appropriate use of a chemical heat-storing unit, and a method for operating the apparatus.
Heat recovery techniques based on utilization of waste heat from various plants have been so far disclosed. For example, "Kogyo Zairyo (Industrial Materials)" Vol. 32, No. 5, discloses A working principle of a heat pump based on a reversible reaction of Ca(OH).sub.2 /CaO system as a chemically heat-storing unit in FIG. 8 in an article entitled "Research and Development of Heat Utilization and Heating Technique and Approach to Their Practical Application." The chemical heat-storing unit disclosed proposes heat recovery based on a conversion reaction, for example, between quick lime CaO and slaked lime Ca(OH).sub.2, allowing a reversible reaction in principle, but the proposed chemical heat-storing unit has problems as a practical apparatus. The first problem is that continuous heat recovery is not taken into consideration; the second is that it is not designed to output the stored energy at an appropriate time when needed, and the third is that no consideration is given specifically to what kind of plant the proposed chemically heat-storing unit should be combined with.